It is the year 2030 and in the rhythm of the seasons the storms of winter move in from the Pacific and cast a gray luminescent canopy over California.
Generations past of Californians were familiar with nature’s cadence, and wary of its capriciousness. They built great dams and aqueducts, engineering marvels that attempted to subdue the elements and bend them to human will.
In the winter and spring, the floodwaters were, for the most part, held back. In the summer, life-giving water from the winter rains and spring snow melt was pumped south through the San Joaquin-Sacramento River Delta to transform the arid San Joaquin Valley into America’s garden and quench the thirst of the megalopolis beyond the Tehachapis.
Now, however, the global warming that scientists first postulated in 1896 and warned about in the 1980s is having a disastrous and costly effect on California.
California’s vast flood control and irrigation projects, designed for 20th-Century climatic conditions, are no longer able to stem the tide of winter floods or provide enough water in the summer.
The sea level has risen at least 1 1/2 feet, creating a vast inland sea in the San Joaquin-Sacramento Delta, usurping unique ecosystems, and causing the collapse of levees that protect rich agricultural lands as well as vital pumping plants that send fresh water to Southern California.
The rising sea level has flooded the beaches and low-lying coastal estuaries, homes and major industrial installations from San Diego to Eureka not protected by seawalls that once were unnecessary.
This vision of what the future may hold for California is, of course, a scenario.
But it is one of several credible California scenarios developed by atmospheric scientists and hydrologists based on their study of global warming hastened by the industrialization of the planet.
Greenhouse gases like carbon dioxide, which are produced by the burning of fossil fuels, accumulate in the atmosphere where they prevent heat energy--radiated from the sun--from escaping the planet. The warming phenomena, known as the “greenhouse effect,” gets its name from the solar warming observed in greenhouses.
The National Academy of Sciences in 1979 said that a doubling of carbon dioxide would raise global temperatures 2.7 to 8.1 degrees Fahrenheit. These estimates were reaffirmed in 1985 by the World Meteorological Organization, the United Nations Environment Program, and the International Council of Scientific Unions.
The Environmental Protection Agency has warned that if current trends continue the climate may change as fast in the next 100 years as it has since the last ice age 18,000 years ago.
Increasingly, the greenhouse problem is being brought home to state and regional policy makers in telling detail by concerned scientists.
At the heart of their concern is that time is running out.
“The greenhouse effect is real. It’s serious and it will shape the environment in which you and I and our children will live,” Irving M. Mintzer of the World Resources Institute told a recent greenhouse conference in San Francisco filled with federal and state officials.
Scientists are worried.
“The types of actions required to slow the rate of climate change are still in the discussion stage, not the action stage. We have yet to take coordinated action on reducing greenhouse gas emissions,” warned Peter H. Gleick of the Berkeley-based Pacific Institute for Studies in Development, Environment and Security.
Said Mintzer, “Most individuals and governments have implicitly assumed that familiar regional climate patterns will remain stable indefinitely. This assumption may no longer be true.”
Slowing the greenhouse effect, scientists said, will buy critical time needed for ecosystems and societies to adjust. Of great concern, he said, is the loss of species--both plant and animal--due to a shift in suitable habitat from one region to another.
Some progress is being made.
In Sacramento, the state Legislature passed and Gov. George Deukmejian signed legislation that directs the state energy commission to study the potential global warming effects on California and make recommendations for state action.
Even a state Senate committee whose purview is solid and hazardous waste convened a special daylong global warming hearing.
Assemblyman Byron Sher (D-Mountain View), who authored the energy commission measure, has also asked a number of state agencies such as the Department of Water Resources to report by early next year on the status of their preparations for global warming and legislative recommendations they may have.
“It seems that every day another member of Congress, another congressional staffer, or another of my constituents wakes up to the fact that we are conducting a dangerous atmospheric experiment that could have grave consequences for the planet,” Rep. George E. Brown Jr. (D-Colton) observed recently.
But while knowledge and concern is building, the accumulation of greenhouse gases is still increasing. Compared to the pre-industrial 1880s, concentrations of carbon dioxide--one of the principal greenhouse gases--have increased 25%. The increase, which continues at a rate of nearly 0.5% a year, is largely due to the combustion of coal, petroleum fuels and natural gas and the burning of tropical forests to clear land for agricultural use.
Some scientists project that the volume of greenhouse gases from pre-industrial levels will double sometime between the year 2030 and 2080. Based on that projection, a study by the U.S. Environmental Protection Agency has suggested these possibilities for California:
- The sea level could rise as much as 3 feet. In the San Francisco Bay Area, this could threaten low-lying commercial and industrial sites on the bay side of the San Francisco Peninsula as far south as San Jose.
- Such a rise would push San Francisco Bay salt water another 2.5 miles to 6 miles deeper into the Sacramento-San Joaquin River Delta. This would increase the volume of the bay’s estuary by 15% and its area by 30%, provided the existing levee system were strengthened and raised. If the levees were left in disrepair and collapsed, the water volume would double and the area under water would triple, creating a shallow but vast inland sea. These changes would have severe consequences for freshwater fish and other species. It would also mean the flooding of thousands of acres of fertile agricultural land, farmhouses and recreational facilities in the delta.
- Even if precipitation levels remain as they are today, more of it would fall as rain than snow because of warmer temperatures. The snow line in the mountains would rise 1,000 feet, shrinking by 30% to 40% the spring snowpack so vital to California’s health and economy. Annual deliveries from the State Water Project that irrigate large sections of the western San Joaquin Valley and bring drinking water to Southern California could decrease by as much as 16% in the late spring and summer.
- The winter runoff in the Sacramento basin would be 17% to 38% greater. The state’s dams would not have enough capacity to both store the added winter runoff and still provide adequate flood protection.
- To meet changing supply and increasing demands, state and federal water agencies would have to modify the Central Valley Project and State Water Project at a cost of billions of dollars.
- Electricity demand could increase, necessitating the construction of additional power plants.
- Air quality would get worse if pollution controls remained the same and temperatures continued to rise. The length of unhealthful ozone levels would triple under one climate scenario. The EPA study said air pollution control agencies may have to re-evaluate the effectiveness of strategies to deal with air pollution on a long-term basis.
“It is difficult to imagine a more sweeping transformation of the Earth as we know it, save that stemming from nuclear war. All aspects of human and natural existence will be affected; and attempts to stabilize greenhouse gases in the atmosphere will require significant lead times before they become effective,” according to a paper prepared for President-elect Bush by Project 88, a public policy study directed by Robert N. Stavins of Harvard University and coordinated by the Environmental Policy Institute.
Humans, of course, can adapt as climatic zones shift hundreds of miles northward. Water management practices can be changed to cope with new circumstance, though they may be costly. Increased demands for electrical power driven by heightened demand for air conditioning can be accommodated, at least in developed countries.
But animals and especially plants would have greater difficulty moving to favorable climates quickly. The EPA noted that since the last ice age, oak trees moved northward from the southeastern United States as the ice sheet retreated. But the warming temperature occurred over the milleniums, time enough for the movement of seeds to keep pace with the northerly advance of the oak’s climate.
The scarcity of water could have a major effect on California’s $15-billion-a-year agricultural economy. Water-intensive crops such as cotton and rice might no longer be practical to grow, scientists said. Crops would require more water because global warming would increase evaporation rates.
Changing public policy to slow the greenhouse effect and buy critical time for ecosystems and societies to adjust may be difficult and very costly. Scientific uncertainity may impede decision making.
While there is confidence among scientists in the models’ general ability of global climatic models to anticipate climatic changes on a global scale, there is less assurance that they can define local and regional effects.
There are also questions, for example, about how effectively the world’s oceans will mitigate the atmospheric warming process by absorbing carbon dioxide. There are other questions, so far raised by a minority of scientists, some of whom suggest that instead of global warming there may actually be global cooling.
Is it possible to undertake programs that may cost billions of dollars in view of such uncertainty?
“Ideally, we’d like to wait another 10 or 15 years. But in some sense, there is the question of can we wait,” observed Michael MacCracken of Lawrence Livermore Laboratory.
Nonetheless, since the first greenhouse predictions, there is little dispute that the Earth will grow warmer.
“We already know enough to be seriously concerned. If we wait for perfect information, then we’re really going to wait too long . . . and be less prepared than we could be,” Gleick said.
Even if scientific knowledge were complete, the decisions would still be enormously difficult.
The emissions of greenhouse gases “come from very fundamental human needs and it will be very difficult to control them,” MacCracken said. He mentioned food, transportation, air conditioning, energy and the need for living space.
Managing the greenhouse effect must involve basic research into the underlying causes and consequences of global warming, as well as research into specific methods of prevention and adaptation. Moreover, because the eventual decisions of what course to take will undoubtedly involve great costs, economic and policy research will be required, Project 88 said.
The United States has yet to fashion explicit policies, even though numerous federal actions--particularly energy policies such as fuel economy requirements on automobiles--have a marked effect on global warming. The average American car pumps 4 tons of carbon dioxide into the atmosphere each year, yet the Reagan Administration delayed tougher fuel economy standards this year.
Some have suggested raising gasoline taxes to reflect the total cost of the fuel, including its environmental costs.
Many look to California for leadership. While it is true that a single nation, much less an individual state, cannot solve a global problem, federal policies have often followed California’s leadership. State air pollution controls and energy efficiency standards for home appliances are examples.
Whatever approaches are taken, scientists agree that the sooner they are taken the better.
“California can expect more climate surprises in their future,” Gleick said. “As we begin to warm the Earth, the climate of tomorrow is going to look different than the climate of today in sometimes dramatic ways. Whether those surprises are bad for California depends a great deal on whether we plan for them today.”
GREENHOUSE EFFECTS ON CALIFORNIA
Scientists studying the greenhouse effect have warned in general about the effect of warmer temperatures on resources, health and food supplies. Now a study has charted projected effects in California. Among them:
WATER RESOURCES Regional warming could cause:
Higher winter, lower summer runoff
Decreased deliveries from Central Valley Project and State Water Project.
Decreased water quality in sub-alpine lakes.
WETLANDS & FISHERIES Rising sea level could cause:
Increased salinity in San Francisco Bay area and delta region.
Gradual inundation of wetlands.
Shift from brackish and freshwater species to more salt-tolerant plants.
Alternation of waterfowl habitat and shifts to marine fish species.
AGRICULTURE Warmer temperatures and carbon dioxide buildup could cause:
Uncertain crop responses.
Increased irrigation demands.
Increase in crop acreage.
AIR QUALITY Warmer temperatures could cause:
Increase in ambient ozone levels.
POWER & ELECTRICITY Warmer temperatures could cause:
Higher power demands.